On September 18, 1810 Chilean leaders decided on limited self-government. Napoleon Bonaparte had imposed his brother Joseph on the throne of Spain and the Chilean establishment – unable to recognize either Joseph or the rebels against France in Spain as legitimate – decided on what was seen as an interim measure until the Spanish throne was restored. This date is now celebrated as Chile's Independence Day. The permanent independence of Chile from Spain was officially achieved on February 12, 1818. The independence process extended f to define the beginning and the end. Traditionally, the period is divided into three stages: Patria Vieja, Reconquista, and Patria Nueva.